added by archaeologs
Alexander Severus was the first emperor who wore a linen shirt ; but the use of so necessary a garment did not become common till long after him. Linen was not worn by Jews, Greeks, or Romans, as any part of their ordinary dress.
CLASSICAL AND ARCHAEOLOGICAL DICTIONARY BY P. AUSTIN NUTTALL, LL.D.
The second major material used in Roman textiles was linen. Linen is a fabric made from flax plants and was widely utilized by the ancient Egyptians. By the time that Roman civilization was flourishing, linen was being produced in Egypt, Syria, and Palestine, as well as to a lesser extent in Europe. This soft, lightweight and breathable material was perfect for accommodating life in the hot and humid Mediterranean.